1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Core driver for the generic pin config portions of the pin control subsystem 4 * 5 * Copyright (C) 2011 ST-Ericsson SA 6 * Written on behalf of Linaro for ST-Ericsson 7 * 8 * Author: Linus Walleij <linus.walleij@linaro.org> 9 */ 10 11 #define pr_fmt(fmt) "generic pinconfig core: " fmt 12 13 #include <linux/array_size.h> 14 #include <linux/debugfs.h> 15 #include <linux/device.h> 16 #include <linux/init.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/slab.h> 20 #include <linux/seq_file.h> 21 22 #include <linux/pinctrl/pinconf-generic.h> 23 #include <linux/pinctrl/pinconf.h> 24 #include <linux/pinctrl/pinctrl.h> 25 26 #include "core.h" 27 #include "pinconf.h" 28 #include "pinctrl-utils.h" 29 30 #ifdef CONFIG_DEBUG_FS 31 static const struct pin_config_item conf_items[] = { 32 PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL, false), 33 PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL, false), 34 PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL, false), 35 PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", "ohms", true), 36 PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 37 "input bias pull to pin specific state", "ohms", true), 38 PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", "ohms", true), 39 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL, false), 40 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL, false), 41 PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL, false), 42 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA", true), 43 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH_UA, "output drive strength", "uA", true), 44 PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec", true), 45 PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL, false), 46 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL, false), 47 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL, false), 48 PCONFDUMP(PIN_CONFIG_MODE_LOW_POWER, "pin low power", "mode", true), 49 PCONFDUMP(PIN_CONFIG_OUTPUT_ENABLE, "output enabled", NULL, false), 50 PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level", true), 51 PCONFDUMP(PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS, "output impedance", "ohms", true), 52 PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector", true), 53 PCONFDUMP(PIN_CONFIG_SLEEP_HARDWARE_STATE, "sleep hardware state", NULL, false), 54 PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL, true), 55 PCONFDUMP(PIN_CONFIG_SKEW_DELAY, "skew delay", NULL, true), 56 }; 57 58 static void pinconf_generic_dump_one(struct pinctrl_dev *pctldev, 59 struct seq_file *s, const char *gname, 60 unsigned int pin, 61 const struct pin_config_item *items, 62 int nitems, int *print_sep) 63 { 64 int i; 65 66 for (i = 0; i < nitems; i++) { 67 unsigned long config; 68 int ret; 69 70 /* We want to check out this parameter */ 71 config = pinconf_to_config_packed(items[i].param, 0); 72 if (gname) 73 ret = pin_config_group_get(dev_name(pctldev->dev), 74 gname, &config); 75 else 76 ret = pin_config_get_for_pin(pctldev, pin, &config); 77 /* These are legal errors */ 78 if (ret == -EINVAL || ret == -ENOTSUPP) 79 continue; 80 if (ret) { 81 seq_printf(s, "ERROR READING CONFIG SETTING %d ", i); 82 continue; 83 } 84 /* comma between multiple configs */ 85 if (*print_sep) 86 seq_puts(s, ", "); 87 *print_sep = 1; 88 seq_puts(s, items[i].display); 89 /* Print unit if available */ 90 if (items[i].has_arg) { 91 seq_printf(s, " (0x%x", 92 pinconf_to_config_argument(config)); 93 if (items[i].format) 94 seq_printf(s, " %s)", items[i].format); 95 else 96 seq_puts(s, ")"); 97 } 98 } 99 } 100 101 /** 102 * pinconf_generic_dump_pins - Print information about pin or group of pins 103 * @pctldev: Pincontrol device 104 * @s: File to print to 105 * @gname: Group name specifying pins 106 * @pin: Pin number specyfying pin 107 * 108 * Print the pinconf configuration for the requested pin(s) to @s. Pins can be 109 * specified either by pin using @pin or by group using @gname. Only one needs 110 * to be specified the other can be NULL/0. 111 */ 112 void pinconf_generic_dump_pins(struct pinctrl_dev *pctldev, struct seq_file *s, 113 const char *gname, unsigned int pin) 114 { 115 const struct pinconf_ops *ops = pctldev->desc->confops; 116 int print_sep = 0; 117 118 if (!ops->is_generic) 119 return; 120 121 /* generic parameters */ 122 pinconf_generic_dump_one(pctldev, s, gname, pin, conf_items, 123 ARRAY_SIZE(conf_items), &print_sep); 124 /* driver-specific parameters */ 125 if (pctldev->desc->num_custom_params && 126 pctldev->desc->custom_conf_items) 127 pinconf_generic_dump_one(pctldev, s, gname, pin, 128 pctldev->desc->custom_conf_items, 129 pctldev->desc->num_custom_params, 130 &print_sep); 131 } 132 133 void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, 134 struct seq_file *s, unsigned long config) 135 { 136 int i; 137 138 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 139 if (pinconf_to_config_param(config) != conf_items[i].param) 140 continue; 141 seq_printf(s, "%s: 0x%x", conf_items[i].display, 142 pinconf_to_config_argument(config)); 143 } 144 145 if (!pctldev->desc->num_custom_params || 146 !pctldev->desc->custom_conf_items) 147 return; 148 149 for (i = 0; i < pctldev->desc->num_custom_params; i++) { 150 if (pinconf_to_config_param(config) != 151 pctldev->desc->custom_conf_items[i].param) 152 continue; 153 seq_printf(s, "%s: 0x%x", 154 pctldev->desc->custom_conf_items[i].display, 155 pinconf_to_config_argument(config)); 156 } 157 } 158 EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); 159 #endif 160 161 #ifdef CONFIG_OF 162 static const struct pinconf_generic_params dt_params[] = { 163 { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, 164 { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, 165 { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, 166 { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 }, 167 { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 }, 168 { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 }, 169 { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, 170 { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, 171 { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, 172 { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, 173 { "drive-strength-microamp", PIN_CONFIG_DRIVE_STRENGTH_UA, 0 }, 174 { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, 175 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 }, 176 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 }, 177 { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, 178 { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, 179 { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, 180 { "low-power-disable", PIN_CONFIG_MODE_LOW_POWER, 0 }, 181 { "low-power-enable", PIN_CONFIG_MODE_LOW_POWER, 1 }, 182 { "output-disable", PIN_CONFIG_OUTPUT_ENABLE, 0 }, 183 { "output-enable", PIN_CONFIG_OUTPUT_ENABLE, 1 }, 184 { "output-high", PIN_CONFIG_OUTPUT, 1, }, 185 { "output-impedance-ohms", PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS, 0 }, 186 { "output-low", PIN_CONFIG_OUTPUT, 0, }, 187 { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, 188 { "sleep-hardware-state", PIN_CONFIG_SLEEP_HARDWARE_STATE, 0 }, 189 { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, 190 { "skew-delay", PIN_CONFIG_SKEW_DELAY, 0 }, 191 }; 192 193 /** 194 * parse_dt_cfg() - Parse DT pinconf parameters 195 * @np: DT node 196 * @params: Array of describing generic parameters 197 * @count: Number of entries in @params 198 * @cfg: Array of parsed config options 199 * @ncfg: Number of entries in @cfg 200 * 201 * Parse the config options described in @params from @np and puts the result 202 * in @cfg. @cfg does not need to be empty, entries are added beginning at 203 * @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg 204 * needs to have enough memory allocated to hold all possible entries. 205 */ 206 static void parse_dt_cfg(struct device_node *np, 207 const struct pinconf_generic_params *params, 208 unsigned int count, unsigned long *cfg, 209 unsigned int *ncfg) 210 { 211 int i; 212 213 for (i = 0; i < count; i++) { 214 u32 val; 215 int ret; 216 const struct pinconf_generic_params *par = ¶ms[i]; 217 218 ret = of_property_read_u32(np, par->property, &val); 219 220 /* property not found */ 221 if (ret == -EINVAL) 222 continue; 223 224 /* use default value, when no value is specified */ 225 if (ret) 226 val = par->default_value; 227 228 pr_debug("found %s with value %u\n", par->property, val); 229 cfg[*ncfg] = pinconf_to_config_packed(par->param, val); 230 (*ncfg)++; 231 } 232 } 233 234 /** 235 * pinconf_generic_parse_dt_config() 236 * parse the config properties into generic pinconfig values. 237 * @np: node containing the pinconfig properties 238 * @pctldev: pincontrol device 239 * @configs: array with nconfigs entries containing the generic pinconf values 240 * must be freed when no longer necessary. 241 * @nconfigs: number of configurations 242 */ 243 int pinconf_generic_parse_dt_config(struct device_node *np, 244 struct pinctrl_dev *pctldev, 245 unsigned long **configs, 246 unsigned int *nconfigs) 247 { 248 unsigned long *cfg; 249 unsigned int max_cfg, ncfg = 0; 250 int ret; 251 252 if (!np) 253 return -EINVAL; 254 255 /* allocate a temporary array big enough to hold one of each option */ 256 max_cfg = ARRAY_SIZE(dt_params); 257 if (pctldev) 258 max_cfg += pctldev->desc->num_custom_params; 259 cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL); 260 if (!cfg) 261 return -ENOMEM; 262 263 parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg); 264 if (pctldev && pctldev->desc->num_custom_params && 265 pctldev->desc->custom_params) 266 parse_dt_cfg(np, pctldev->desc->custom_params, 267 pctldev->desc->num_custom_params, cfg, &ncfg); 268 269 ret = 0; 270 271 /* no configs found at all */ 272 if (ncfg == 0) { 273 *configs = NULL; 274 *nconfigs = 0; 275 goto out; 276 } 277 278 /* 279 * Now limit the number of configs to the real number of 280 * found properties. 281 */ 282 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 283 if (!*configs) { 284 ret = -ENOMEM; 285 goto out; 286 } 287 288 *nconfigs = ncfg; 289 290 out: 291 kfree(cfg); 292 return ret; 293 } 294 EXPORT_SYMBOL_GPL(pinconf_generic_parse_dt_config); 295 296 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 297 struct device_node *np, struct pinctrl_map **map, 298 unsigned int *reserved_maps, unsigned int *num_maps, 299 enum pinctrl_map_type type) 300 { 301 int ret; 302 const char *function; 303 struct device *dev = pctldev->dev; 304 unsigned long *configs = NULL; 305 unsigned int num_configs = 0; 306 unsigned int reserve, strings_count; 307 struct property *prop; 308 const char *group; 309 const char *subnode_target_type = "pins"; 310 311 ret = of_property_count_strings(np, "pins"); 312 if (ret < 0) { 313 ret = of_property_count_strings(np, "groups"); 314 if (ret < 0) 315 /* skip this node; may contain config child nodes */ 316 return 0; 317 if (type == PIN_MAP_TYPE_INVALID) 318 type = PIN_MAP_TYPE_CONFIGS_GROUP; 319 subnode_target_type = "groups"; 320 } else { 321 if (type == PIN_MAP_TYPE_INVALID) 322 type = PIN_MAP_TYPE_CONFIGS_PIN; 323 } 324 strings_count = ret; 325 326 ret = of_property_read_string(np, "function", &function); 327 if (ret < 0) { 328 /* EINVAL=missing, which is fine since it's optional */ 329 if (ret != -EINVAL) 330 dev_err(dev, "%pOF: could not parse property function\n", 331 np); 332 function = NULL; 333 } 334 335 ret = pinconf_generic_parse_dt_config(np, pctldev, &configs, 336 &num_configs); 337 if (ret < 0) { 338 dev_err(dev, "%pOF: could not parse node property\n", np); 339 return ret; 340 } 341 342 reserve = 0; 343 if (function != NULL) 344 reserve++; 345 if (num_configs) 346 reserve++; 347 348 reserve *= strings_count; 349 350 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 351 num_maps, reserve); 352 if (ret < 0) 353 goto exit; 354 355 of_property_for_each_string(np, subnode_target_type, prop, group) { 356 if (function) { 357 ret = pinctrl_utils_add_map_mux(pctldev, map, 358 reserved_maps, num_maps, group, 359 function); 360 if (ret < 0) 361 goto exit; 362 } 363 364 if (num_configs) { 365 ret = pinctrl_utils_add_map_configs(pctldev, map, 366 reserved_maps, num_maps, group, configs, 367 num_configs, type); 368 if (ret < 0) 369 goto exit; 370 } 371 } 372 ret = 0; 373 374 exit: 375 kfree(configs); 376 return ret; 377 } 378 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 379 380 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 381 struct device_node *np_config, struct pinctrl_map **map, 382 unsigned int *num_maps, enum pinctrl_map_type type) 383 { 384 unsigned int reserved_maps; 385 struct device_node *np; 386 int ret; 387 388 reserved_maps = 0; 389 *map = NULL; 390 *num_maps = 0; 391 392 ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map, 393 &reserved_maps, num_maps, type); 394 if (ret < 0) 395 goto exit; 396 397 for_each_available_child_of_node(np_config, np) { 398 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 399 &reserved_maps, num_maps, type); 400 if (ret < 0) { 401 of_node_put(np); 402 goto exit; 403 } 404 } 405 return 0; 406 407 exit: 408 pinctrl_utils_free_map(pctldev, *map, *num_maps); 409 return ret; 410 } 411 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 412 413 void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 414 struct pinctrl_map *map, 415 unsigned int num_maps) 416 { 417 pinctrl_utils_free_map(pctldev, map, num_maps); 418 } 419 EXPORT_SYMBOL_GPL(pinconf_generic_dt_free_map); 420 421 #endif 422